The Laws of Prayer (The morning services) (15)

1. A person should wait for a short time before praying so that he will be able to concentrate his mind on Hashem. Even though it is an act of piety to wait a full hour, everybody is not obligated to do so. It suffices to wait a short while, which is the time it takes to walk eight Tefachim (between 64 and 80 centimeters). (Shulchan Aruch and Mishne Berurah 90)

2. He should also wait for the same amount of time after prayers, so that it does not look like a burden from which he is hurrying to leave. (ibid)